Electrical switch



y 1, 1962 L B. RONK 3,032,627

ELECTRICAL SWITCH Filed March 5, 1959 INVENTOR ATTORNEY LEROY B RONK nite Staes 3,032,627 ELECTRICAL SWITCH 'Leroy B. Ronk, Nokomis, 11]., assignor to System Analyzer Corp, Nokomis, 111., a corporation of Wisconsin Filed Mar. 5, 1959, Ser. No. 797,491 3 Claims. (Cl. 200-87) This invention relates to new and useful improve- :ments in an electrical switch and more particularly to .ments may be obviated.

Another object is to provide an arc interrupting switch .having a pair of relatively movable contacts, one of which comprises at least two relatively movable elements which sequentially cooperate with the other contact, the element last engaging said other contact being adjacent an arcing horn and movable in closer proximity thereto as it moves away from said other contact, whereby an are between said other contact and said element last engaged therewith is transferred by a magnetic field action to said arcing horn and extinguished at zero voltage potential as the horn and element move in closer I proximity during the circuit interrupting operations.

More precisely it is an object to provide, for use in an alternating capacitive circuit, a magnetically operated .double pole switch in which arcing is prevented between main current carrying contacts by transfer of the arc, under the influence of a magnetic field, to relatively movable arcing terminals, the arc thereafter shortened as the voltage potential approaches Zero, thereby reducing to a minimum the audibility of arc interruption as the current reaches zero value.

Other advantages will become apparent as the description of the drawings progress, in which FIG. 1 is a view in side elevation, partly in section, illustrating an embodiment of my invention.

FIG. 2 is a plan view as seen from above relative to FIG. 1.

FIGS. 3 and 4 are fragmentary views of a portion of the device shown in FIGS. 1 and 2, illustrating the se quence of movement of the switch contacts and arcing terminals.

In the modification herein disclosed, the switch structure comprises an insulating base plate 1 upon which are mounted a combination arcing horn 2 and switch terminal contact 3, a solenoid coil 4 and a switch terminal contact 5. A contact bar 6 extends from a point above the switch contact 3 to a point above the switch terminal contact and is carried by an armature 7 pivotally mounted at 8 on the actuator 9. When the solenoid coil 4 is deenergized, a coil spring 11, secured at one end to base plate 1 and at the other end to the bar 6, maintains the bar 6 in the position shown in FIG. 1

The switch contact 3 comprises an L-shaped member 12 secured to the base plate 1 by means of bolt and nut assemblies 13 and 14 and an angle piece pivotally carried by the upper end of the member 12 and retained in the position shown by means of loosely fitting pin 16 extend ing through the member 12 and the downwardly extending leg 20 of the piece 15'. A coil spring 17 is mounted to react between the pin 16 and member 12. A conductive cable 18 electrically connects the horizontally extending contact arm 19 of the piece 15 and the foot portion 21 of the member 12. The arcing horn 3,932,627 fiatented May 1, 1962 ice 2 includes a foot portion 22 clamped to the base plate 1 by means of the foot portion 21 on the member 12 and the bolt and nut assemblies 13 and 14. The upward extension 23 or" the arcing horn 2 is inclined toward the adjacent end of contact arm 19 and terminates in an angled portion 24- inclined over the contact arm 19.

The switch contact 5 is similar in construction to switch contact 3 and comprises an L-shaped member 25 having its foot portion 31 secured to the base plate 1 by means of bolt and nut assemblies 32 and 33. Pivotally mounted on the upper end of the member 25 is an L-shaped contact arm 34. A loosely fitting pin 35 extends through the vertically extending portion 36 of the member 25 and the downwardly extending adjacent portion 37 of the contact arm 34. Mounted on the pin 35 is a coil spring 38 cooperating with the pin to bias the portions 36 and 37 of the contact 5 into parallel and adjacent contact relation. A conductive cable 39 electrically connects the foot portion 31 of the switch contact 5 and the contact arm 34.

The contact bar 6 terminates at each end in a curved contact surface 41 and 42, respectively. Mounted on the bar 6 adjacent the Surface 41 is an L-shaped auxiliary contact finger 43 having the contact portion 44 extending downwardly to a point below the contact surface 41. A loosely fitting pin 45 extends through the bar 6 and the adjacent portion of the finger 43. A coil spring 46 mounted on the pin '45 cooperates therewith to bias the adjacent portions of the bar 6 and finger 43 into parallel adjacent contact.v A flexible conductive cable 47 electrically connects the bar 6 and finger 43. A flexible cable 48 connected at 46 with the bar 6 extends to the terminal post 51 on the base plate 1.

An arc shield 52 embracing armature 7 is disposed between the bar 6 and the armature 7 and is secured thereto at points 53 and is provided with a downwardly extending shield portion 54 disposed between the contact arm 15 and the upstanding solenoid core portion 55. A post 56 of insulating material is mounted between the core portion 55 and the downwardly extending leg 20 of the piece 15 to limit the pivotal movement of the leg 20 after contact is made between the contact surface 41 on the bar 6 and the contact arm 19 of the piece 15. Leads arranged in pairs 57 and 58 extending from the solenoid 4 are respectively connected with terminal posts 59 and 61 mounted on the base plate 1.

Preferably the contact 3, contact 5, and bar 6 are of copper and the arcing horn 2 and contact finger 43 are of iron. Bolts 14 and 33 may serve as terminals for connecting electric lines to the contacts 3 and 5, respectively.

The double pole switch herein disclosed is adapted for use in an AC. capacitance electric circuit wherein the current leads the voltage through zero value. However, those skilled in the art will readily understand that the switch may be adapted for use in an inductive circuit wherein the current lags the voltage through zero value by slanting the angle portion 24 of the arcing horn 2 away from the contact finger 43 rather than toward it as shown in the drawings.

Operation of the switch is as follows:

As shown in FIGS. 1 and 2, the contact bar 6 is in open position relative to switch terminal contact 3 and in closed position relative to the switch terminal contacts 5 when the solenoid coil 4 is deenergized. Upon energization of the solenoid coil 4 the armature 7 is pivoted downwardly about its pivot 8 and the switch bar 6 carried thereby moves in a counterclockwise direction as viewed in FIG. 1 thereby opening the circuit through the switch terminal contact 5 and closing the capacitance circuit through switch terminal contact 3.

As the bar 6 moves toward the switch terminal contact 3 3, the contact portion 44 of the contact finger 43 first engages contact arm 19 on the angle piece 15 thereby closing the capacitance circuit through the switch terminal contact 3 and flexible cable 48. Further movement of the bar 6 counterclockwise produces a wiping action between the contacting surfaces of arm 19 and finger 43 and rotates angle piece 15 and finger 43 against the bias of the springs 17 and 46, respectively. Further movement of the bar 6 counterclockwise engages the contact surface 41 with the arm 19 with a wiping contact and provides an electric path of less resistance than through the finger 43.

When the solenoid coil '4 is deenergized, the spring 11 produces a clockwise motion of the bar 6, causing first a break between the contact surface 41 and arm 19 and subsequently between the contact portion 44 on the finger 43 and the arm 19. As the portion 44 and arm 19 separate, an arc is drawn therebetween and the magnetic field incident to the flow of current through the conducting members transfers the are from the arm 19 to the arcing horn 2. The are thus transferred seeks the shortest path between the finger 43 and the angle portion 24 on the arcing horn and is thereafter extinguished as the current value reaches zero.

From the foregoing it will be seen that an arrangement of the elements has been provided in which the following novel results are obtained, namely:

As the current drops sharply through zero, collapse of the arc minimizes the resulting report and reduces to a minimum, the pitting action of the are between the main contacts as well as the transfer contacts, and as a result, any pitting action of consequence will occur between the iron finger and arcing horn where damage to the respective. elements is of little importance. Furthermore, the manner in which the arc is interrupted insures a relatively long life of usefulness of the main contact between the portion 41 and arm 19 and the hinging action of the angle piece 15, finger '43 and the contact arm 34 permits a wiping contact as the circuits are closed and opened, thus providing clean contact surfaces for the flow of current.

It will be understood, that as the bar 6 rotates clockwise upon deenergization of the solenoid coil 4, a circuit through flexible cable 48, bar 6 and terminal contact is closed upon engagement of contact surface 42 and arm 34.

Although I have disclosed a specific embodiment of my invention, it will be understood that I do not limit the scope of the appended claims to such embodiment unless the terms thereof justify such limitations.

I claim:

1. In an electrical switch, the combination comprising: an electromagnet having a movable armature; a movablecontact bar actuated in a rocking motion by the armature and having first and second movable contacts at opposite ends thereof which are alternatively raised and lowered in arcuate paths upon rocking motion of the bar; .a first stationary contact disposed in facing relation to the movable contact; a second stationary contact disposed in, facing relation to the second movable contact, said rocking motion of, the bar causing the second movable contact tobe. moved alternatively between open and closed positions with respect to the second stationary contact, there being a gap between the second movable contact and the second stationary contact when the second movable contact is in open position; and an arc horn electrically connected to the second stationary contact and conformed to extend in a substantially arcuate manner along a path that is substantially concentric with the path of travel of the second movable contact and spaced therefrom a distance that is less than the gap between the second movable contact and the second stationary contact when the second movable contact is in open position.

2. In an electrical switch, the combination comprising:

4 an electromagnet having a pivotally mounted armature; a movable contact bar that is actuated in a rocking motion by the armature having first and segnd movable contacts at opposite ends thereof which are alternatively raised and lowered in arcuate paths upon rocking motion of the contact bar; a first stationary contact disposed in facing relationship to the first movable contact and arranged to yield upon engagement by the first movable contact whereby the contact bar is caused to have an overtravel; a second stationary contact disposed in tacing relation to the second movable contact; and an arc horn electrically connected to the second stationary contact and extending in a substantially arcuate manner along a path substantially concentric with the path of movement of the second movable contact whereby an arc path is maintained between the arc horn and the second movable contact that is shorter than the maximum gap between the second movable contact and the second stationary contact caused by the overtravel of the contact bar.

3. In an electrical switch, the combination comprising: an electromagnet having a pivotally mounted armature; a movable contact bar actuated in a rocking motion by the armature and having first and second movable contacts at opposite ends thereof; an auxiliary contact mounted on said contact bar at the end thereof bearing the second movable contact, said auxiliary contact being displaceable with respect to the contact bar and having a contact finger that is resilient-1y biased toward an extended position with respect to the second movable contact, said auxiliary contact and said first and second movable contacts being alternatively raised and lowered in arcuate paths upon rocking motion of the contact bar; a first stationary contact disposed in facing relationship to the first movable contact and arranged to yield upon engagement by the first movable contact whereby the contact bar is caused to have an overtravel'; a second stationary contact disposed in facing relationship to the second movable contact and the auxiliary contact, said second stationary contact having an upstanding member forming a pivot at its end and an angular movable contact arm turning over the pivot with one end extending alongside the upstanding member and resilient-1y biased toward engagement with the upstanding member, the other end of the contact arm being adapted to be engaged by the auxiliary contact and the second movable contact; and an arc horn electrically connected to the second stationary contact and extending in a substantially arcuate manner along a path substantially concentric with the path of movement of the auxiliary contact whereby upon disengagement of the auxiliary contact and the second movable contact from the second stationary contact an arc path is maintained between the auxiliary contact and the arc horn that is shorter than the maximum gap between the second movable contact and the second stationary contact.

References Qited in the file of this patent UNITED STATES PATENTS 1,244,225 Mayer Oct. 23, 1917 1,596,417 Eschholz et a1 Aug. 17, 1926 1,901,363 Bnrnham Mar. 14, 1933 2,285,643 Beiersdorf June 2, 1942 2,341,931 Lloyd Feb. 15, 1944 2,375,216 Eaton May 8, 1945 2,391,692 'Estes Dec. 25,1945 2,545,341 Caswell Mar. 13, 1951 2,564,246 Bourne Aug. 14,1951 2,664,479 Pokorny Dec. 29, 1953 2,840,662 lessee June 24, 1958 2,882,460 Sauer Apr. 14, 1959 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3,032,627 May 1,, 1962 Leroy B. ,Ronk

It is hereby certified that error appears in the ebove numbered patent requiring correction and that the 'said Letters Patent should read as corrected below.

Column 3 line 56, after -'-'the' insert first Signed and sealed this 4th day of September 1962.

(SEAL) lttest:

ZRNEST w. SWIDER DAVID LADD \ttesting Officer Commissioner of Patents 

